Cobalt Fast-Neutron Cross Sections

Elastic and inelastic neutron scattering cross sections of cobalt were measured from incident energies of 1.8 to 4.0 MeV including the excitation of states at 1.10 ± 0.01, 1.20 ± 0.01, 1.30 ± 0.01, 1.43 ± 0.01, 1.46 ± 0.02, 1.72 ± 0.02, 2.06 ± 0.02, 2.09 ± 0.02, 2.16 ± 0.03, 2.35 ± 0.05, and 2.50 ± 0.05 MeV. Total neutron cross sections were measured from 2.0 to 4.5 MeV. The experimental results and previously reported values are used to deduce an optical-statistical model which is descriptive of measured values to ∼20.0 MeV. The observed inelastic scattering cross sections are related to the level structure of the target isotope and are shown consistent with a nuclear structure model based upon a proton hole in the ƒ_7/2 shell strongly coupled to a spherical core. A resolution to the previous ambiguities in f^π assignments is suggested. The experimental and calculational results are compared with the cross-section values given by ENDF/B-III.